Displaying publications 1 - 20 of 292 in total

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  1. Sultan MT, Butt MS, Karim R, Ahmed W, Kaka U, Ahmad S, et al.
    PMID: 26385559 DOI: 10.1186/s12906-015-0853-7
    Nigella sativa is an important component of several traditional herbal preparations in various countries. It finds its applications in improving overall health and boosting immunity. The current study evaluated the role of fixed and essential oil of Nigella sativa against potassium bromate induced oxidative stress with special reference to modulation of glutathione redox enzymes and myeloperoxidase.
    Matched MeSH terms: Glutathione/metabolism; Glutathione Peroxidase/metabolism; Glutathione Reductase/metabolism; Glutathione Transferase/metabolism
  2. Chen J, Jiang C, Huang H, Wei S, Huang Z, Wang H, et al.
    Pestic Biochem Physiol, 2017 Nov;143:201-206.
    PMID: 29183593 DOI: 10.1016/j.pestbp.2017.09.012
    The evolution of weed-resistant species threatens the sustainable use of glyphosate, which is the most important herbicide widely used in agriculture worldwide. Moreover, the high glyphosate resistance (>180-fold based on LD50) of Eleusine indica found in Malaysia, which carries a double mutation in its 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), made the control of this species more difficult. By contrast, the same species carrying the same double mutation in EPSPS (T102I+P106S) but found in China only shows a resistance level of not more than 14-fold based on GR50. The resistance level of this population is four times higher than that of the population carrying a single mutation (P106L). Although the members of this population survive under a high glyphosate dosage of 10,080gaeha-1, their growth was significantly inhibited by glyphosate under the recommend dose (840gaeha-1), where in the fresh weight was 85.4% of the control. EPSPS expression, relative copy number, and EPSPS activity in this population were similar to those of the susceptible population. In addition, the expression of two glutathione transferase (GST) genes (GST-U8 and GST-23) and the enzyme activity of the GST in this population did not significantly differ from those of the susceptible population. This finding is important in elucidating the resistance of the naturally evolved glyphosate-resistant (GR) weed species carrying a double mutation in EPSPS to glyphosate.
    Matched MeSH terms: Glutathione Transferase/genetics; Glutathione Transferase/metabolism
  3. Mohd Ridzuan MA, Noor Rain A, Zhari I, Zakiah I
    Trop Biomed, 2005 Dec;22(2):155-63.
    PMID: 16883282 MyJurnal
    In the present study we examined the effect of E. longifolia methanol extract (TA164) on the GSH levels of P. falciparum infected erythrocytes and uninfected erythrocytes. Our study on parasite growth shows the IC50 and IC75 values of TA164 to be 0.17 g/ml and 6 g/ml respectively while for BSO was 25.5 g/ml and 46.5 g/ml respectively. About 95% to 100% growth inhibition of P. falciparum infected erythrocyte was observed when treated with TA164 and BSO at 16 g/ml and 64 g/ml respectively. The study on GSH contents indicated that non-infected erythrocytes treated with 6 g/ml (IC75 values) of TA164 at 24 hours incubation showed less GSH content as compared to non-treated erythrocytes. A similar observation was seen on treated trophozoite infected erythrocyte (10% parasitemia) when treated with 6 g/ml at 3 hours incubation. Analysis of the GSH contents of parasite compartments treated with TA164 at the same concentration (6 g/ml) for 3 hours incubation indicated a reduction of GSH contents. At the same concentration, TA164 did not affect the GSH contents of enriched trophozoite infected erythrocytes (60-70% parasitemia). TA164 did affect the GSH content of non-infected erythrocyte at 24 hours (accept IC50 value) as well as the parasite compartments (trophozoite infected erythrocyte and parasite itself) but fails to affect the GSH content of enriched trophozoite infected erythrocyte.
    Matched MeSH terms: Glutathione/metabolism*
  4. Abd Aziz CB, Ahmad Suhaimi SQ, Hasim H, Ahmad AH, Long I, Zakaria R
    J Integr Med, 2019 Jan;17(1):66-70.
    PMID: 30591413 DOI: 10.1016/j.joim.2018.12.002
    OBJECTIVE: This study was done to determine whether Tualang honey could prevent the altered nociceptive behaviour, with its associated changes of oxidative stress markers and morphology of the spinal cord, among the offspring of prenatally stressed rats.

    METHODS: Pregnant rats were divided into three groups: control, stress, and stress treated with Tualang honey. The stress and stress treated with Tualang honey groups were subjected to restraint stress from day 11 of pregnancy until delivery. Ten week old male offspring (n = 9 from each group) were given formalin injection and their nociceptive behaviours were recorded. After 2 h, the rats were sacrificed, and their spinal cords were removed to assess oxidative stress activity and morphology. Nociceptive behaviour was analysed using repeated measures analysis of variance (ANOVA), while the levels of oxidative stress parameters and number of Nissl-stained neurons were analysed using a one-way ANOVA.

    RESULTS: This study demonstrated that prenatal stress was associated with increased nociceptive behaviour, changes in the oxidative stress parameters and morphology of the spinal cord of offspring exposed to prenatal stress; administration of Tualang honey reduced the alteration of these parameters.

    CONCLUSION: This study provides a preliminary understanding of the beneficial effects of Tualang honey against the changes in oxidative stress and neuronal damage in the spinal cord of the offspring of prenatally stressed rats.

    Matched MeSH terms: Glutathione/metabolism
  5. Ramalingam A, Santhanathas T, Shaukat Ali S, Zainalabidin S
    PMID: 31726798 DOI: 10.3390/ijerph16224445
    Prolonged exposure to nicotine accelerates onset and progression of renal diseases in habitual cigarette smokers. Exposure to nicotine, either via active or passive smoking is strongly shown to enhance renal oxidative stress and augment kidney failure in various animal models. In this study, we investigated the effects of resveratrol supplementation on nicotine-induced kidney injury and oxidative stress in a rat model. Male Sprague-Dawley rats were given nicotine (0.6 mg/kg, i.p.) alone or in combination with either resveratrol (8 mg/kg, i.p.), or angiotensin II type I receptor blocker, irbesartan (10 mg/kg, p.o.) for 28 days. Upon completion of treatment, kidneys were investigated for changes in structure, kidney injury markers and oxidative stress. Administration of nicotine alone for 28 days resulted in significant renal impairment as shown by marked increase in plasma creatinine, blood urea nitrogen (BUN) and oxidative stress. Co-administration with resveratrol however successfully attenuated these changes, with a concomitant increase in renal antioxidants such as glutathione similar to the conventionally used angiotensin II receptor blocker, irbesartan. These data altogether suggest that targeting renal oxidative stress with resveratrol could alleviate nicotine-induced renal injury. Antioxidants may be clinically important for management of renal function in habitual smokers.
    Matched MeSH terms: Glutathione/metabolism
  6. Tan CK, Ali ZM, Ismail I, Zainal Z
    ScientificWorldJournal, 2012;2012:474801.
    PMID: 22919322 DOI: 10.1100/2012/474801
    The objective of the present study was to simultaneously evaluate the effect of a postharvest treatment on the pepper's antioxidant content and its ability to retain its economical value during the postharvest period. The fruits were pretreated by modified atmosphere packaging (MAP) with or without treatment with 1-methylcyclopropene (1-MCP) before cold storage at 10°C. Changes in the levels of non-enzymatic antioxidants, including the total phenolic, ascorbic acid levels and the total glutathione level, as well as enzymatic antioxidants, including ascorbate peroxidase (APX), glutathione reductase (GR), and catalase (CAT), were determined. Both treatments successfully extended the shelf life of the fruit for up to 25 days, and a high level of antioxidant capacity was maintained throughout the storage period. However, 1-MCP treatment maintained the high antioxidant capacity for a longer period of time. The 1-MCP-treated peppers maintained high levels of phenolic content, a high reduced glutathione (GSH)/oxidised glutathione (GSSG) ratio, decreased levels of ascorbic acid and CAT activity, and increased levels of APX and GR compared with the peppers that were not treated with 1-MCP. The overall results suggested that a combination of 1-MCP and MAP was the most effective treatment for extending shelf life while retaining the nutritional benefits.
    Matched MeSH terms: Glutathione/metabolism; Glutathione Reductase/metabolism
  7. Karen-Ng LP, Marhazlinda J, Rahman ZA, Yang YH, Jalil N, Cheong SC, et al.
    Asian Pac J Cancer Prev, 2011;12(5):1161-6.
    PMID: 21875259
    Dietary isothiocyanates (ITCs) found in cruciferous vegetables (Brassica spp.) has been reported to reduce cancer risk by inducing phase II conjugating enzymes, in particular glutathione S-transferases (GSTs). This case-control study was aimed at determining associations between dietary ITCs, GSTs polymorphisms and risk habits (cigarette smoking, alcohol drinking and betel-quid chewing) with oral cancer in 115 cases and 116 controls. Information on dietary ITC intake from cruciferous vegetables was collected via a semi-quantitative food frequency questionnaire (FFQ). Peripheral blood lymphocytes were obtained for genotyping of GSTM1, GSTT1 and GSTP1 using PCR multiplex and PCR-RFLP. Chi-square and logistic regression were performed to determine the association of ITC and GSTs polymorphism and risk of oral cancer. When dietary ITC was categorized into high (greater than/equal to median) and low (less than median) intake, there was no significant difference between cases and control group. Logistic regression yielding odd ratios resulted in no significant association between dietary ITC intake, GSTM1, GSTT1 or GSTP1 genotypes with oral cancer risk overall. However, GSTP1 wild-type genotype was associated with later disease onset in women above 55 years of age (p= 0.017). Among the men above 45 years of age, there was clinical significant difference of 17 years in the age of onset of oral cancer between GSTP1 wild-type + low ITC intake and GSTP1 polymorphism + high ITC intake (p= 0.001). Similar conditions were also seen among men above 45 years of age with risk habits like drinking and chewing as the earlier disease onset associated with GSTP1 polymorphism and high ITC intake (p< 0.001). This study suggests that combination effects between dietary ITCs, GSTP1 polymorphism and risk habits may be associated with the risk of oral cancer and modulate the age of disease onset.
    Matched MeSH terms: Glutathione Transferase/genetics*; Glutathione S-Transferase pi/genetics*
  8. Kwan PP, Banerjee S, Shariff M, Yusoff FM
    Vet World, 2019 Sep;12(9):1416-1421.
    PMID: 31749575 DOI: 10.14202/vetworld.2019.1416-1421
    Background and Aim: Malachite green (MG) is an effective antiparasitic and antifungal chemical for treatment of fish. However, MG is reported to be a potential carcinogen. Yet, it is widely used in aquaculture despite its prohibition for use in food-producing animals by the EU and USFDA. The present study quantified MG residues and evaluated the oxidative stress in red tilapia when exposed to subacute and sublethal concentrations of MG.

    Materials and Methods: Red tilapia exposed to subacute (0.105 mg/L for 20 days) and sublethal (0.053 mg/L for 60 days) concentrations were evaluated for total plasma protein, total immunoglobulin, nitroblue tetrazolium activity, malondialdehyde, reduced glutathione (GSH), and catalase (CAT) activity levels. The residues of MG and leuco-MG (LMG) were also quantified in the fish muscles using liquid chromatography-tandem mass spectrometry.

    Results: Fish exposed to subacute concentration showed higher CAT on day 10 in the liver and days 5 and 15 in the spleen, whereas in fish exposed to the sublethal concentration, higher levels of GSH were observed on day 1 in the kidney and day 50 in the spleen. Fish muscle was able to accumulate the sum of MG and LMG of 108.04 µg/kg for subacute (day 20) and 82.68 µg/kg for sublethal (day 60).

    Conclusion: This study showed that red tilapia was able to adapt to the stress caused by exposure to MG at sublethal concentration.

    Matched MeSH terms: Glutathione
  9. Makpol S, Yeoh TW, Ruslam FA, Arifin KT, Yusof YA
    PMID: 23948056 DOI: 10.1186/1472-6882-13-210
    Human diploid fibroblasts (HDFs) undergo a limited number of cellular divisions in culture and progressively reach a state of irreversible growth arrest, a process termed cellular ageing. Even though beneficial effects of Piper betle, Chlorella vulgaris and tocotrienol-rich fraction (TRF) have been reported, ongoing studies in relation to ageing is of interest to determine possible protective effects that may reverse the effect of ageing. The aim of this study was to evaluate the effect of P. betle, C. vulgaris and TRF in preventing cellular ageing of HDFs by determining the activity of antioxidant enzymes viz.; catalase, superoxide dismutase (SOD) and glutathione peroxidase.
    Matched MeSH terms: Glutathione Peroxidase/metabolism
  10. Aliahmat NS, Noor MR, Yusof WJ, Makpol S, Ngah WZ, Yusof YA
    Clinics (Sao Paulo), 2012 Dec;67(12):1447-54.
    PMID: 23295600
    OBJECTIVE: The aim of this study was to determine the erythrocyte antioxidant enzyme activity and the superoxide dismutase, catalase, glutathione peroxidase, and plasma malondialdehyde levels in aging mice and to evaluate how these measures are modulated by potential antioxidants, including the tocotrienol-rich fraction, Piper betle, and Chlorella vulgaris.

    METHOD: One hundred and twenty male C57BL/6 inbred mice were divided into three age groups: young (6 months old), middle-aged (12 months old), and old (18 months old). Each age group consisted of two control groups (distilled water and olive oil) and three treatment groups: Piper betle (50 mg/kg body weight), tocotrienol-rich fraction (30 mg/kg), and Chlorella vulgaris (50 mg/kg). The duration of treatment for all three age groups was two months. Blood was withdrawn from the orbital sinus to determine the antioxidant enzyme activity and the malondialdehyde level.

    RESULTS: Piper betle increased the activities of catalase, glutathione peroxidase, and superoxide dismutase in the young, middle, and old age groups, respectively, when compared to control. The tocotrienol-rich fraction decreased the superoxide dismutase activity in the middle and the old age groups but had no effect on catalase or glutathione peroxidase activity for all age groups. Chlorella vulgaris had no effect on superoxide dismutase activity for all age groups but increased glutathione peroxidase and decreased catalase activity in the middle and the young age groups, respectively. Chlorella vulgaris reduced lipid peroxidation (malondialdehyde levels) in all age groups, but no significant changes were observed with the tocotrienol-rich fraction and the Piper betle treatments.

    CONCLUSION: We found equivocal age-related changes in erythrocyte antioxidant enzyme activity when mice were treated with Piper betle, the tocotrienol-rich fraction, and Chlorella vulgaris. However, Piper betle treatment showed increased antioxidant enzymes activity during aging.

    Matched MeSH terms: Glutathione Peroxidase/blood
  11. Shakirin FH, Azlan A, Ismail A, Amom Z, Yuon LC
    Oxid Med Cell Longev, 2012;2012:840973.
    PMID: 22685623 DOI: 10.1155/2012/840973
    The aim of this paper was to compare the effects of pulp and kernel oils of Canarium odontophyllum Miq. (CO) on lipid profile, lipid peroxidation, and oxidative stress of healthy rabbits. The oils are rich in SFAs and MUFAs (mainly palmitic and oleic acids). The pulp oil is rich in polyphenols. Male New Zealand white (NZW) rabbits were fed for 4 weeks on a normal diet containing pulp (NP) or kernel oil (NK) of CO while corn oil was used as control (NC). Total cholesterol (TC), HDL-C, LDL-c and triglycerides (TG) levels were measured in this paper. Antioxidant enzymes (superoxide dismutase and glutathione peroxidise), thiobarbiturate reactive substances (TBARSs), and plasma total antioxidant status (TAS) were also evaluated. Supplementation of CO pulp oil resulted in favorable changes in blood lipid and lipid peroxidation (increased HDL-C, reduced LDL-C, TG, TBARS levels) with enhancement of SOD, GPx, and plasma TAS levels. Meanwhile, supplementation of kernel oil caused lowering of plasma TC and LDL-C as well as enhancement of SOD and TAS levels. These changes showed that oils of CO could be beneficial in improving lipid profile and antioxidant status as when using part of normal diet. The oils can be used as alternative to present vegetable oil.
    Matched MeSH terms: Glutathione Peroxidase/metabolism
  12. Jayasingh Chellammal HS, Veerachamy A, Ramachandran D, Gummadi SB, Manan MM, Yellu NR
    Biomed Pharmacother, 2019 Jan;109:1454-1461.
    PMID: 30551397 DOI: 10.1016/j.biopha.2018.10.189
    The progressive accumulation of amyloid beta (Aβ) peptide is neurotoxic and leads to Alzheimer's type dementia. Accumulation of Aβ has been associated with dysfunction of hypothalamic-pituitary-adrenal (HPA) axis and elevated pro-inflammatory cytokines. In this study, we investigated the effect of 1`δ-1`-acetoxyeugenol acetate (DAEA), isolated from Alpinia galanga (L.), on Aβ(25-35) induced neurodegeneration in mice. Mice were treated with three different doses of DAEA (12.5 mg/kg, 25 mg/kg and 50 mg/kg) for 28 days. Aβ(25-35) was injected by intracerebroventricular (i.c.v.) injection on the 15th day of 28 days. Open field, water maze and step-down inhibitory tests were performed on the 27th day to determine the habituation memory, spatial learning, and short- and long-term memory, respectively. Acetylcholinesterase (AChE), Corticosterone, biogenic amines (serotonin and dopamine), tumour necrosis factor-α (TNF-α), and antioxidant parameters such as superoxide dismutase, catalase, glutathione peroxidase and vitamin C were evaluated in brain homogenates after behavioural tests to ascertain the cognitive improvement through neuro-immune-endocrine modulation. The DAEA treatment with 25 mg/kg and 50 mg/kg resulted in significant (p < 0.001) improvement of habituation memory and step-down inhibitory avoidance task. In spatial learning, the cognitive improvement was significantly improved (p < 0.001) by reduction in escape latency. In the biochemical study, the significant (p < 0.001) reduction of AChE indicates the preeminent neuroprotection. Corticosterone and TNF-α were significantly (p < 0.01) reduced and biogenic amines were increased with antioxidant markers, which signify the potential influence of DAEA on neuroprotection. Our investigation revealed that the drug DAEA attenuates stress mediated through the HPA axis and regulates the neuroendocrine and neuroimmune function to improve the cognition. DAEA could be a potential lead candidate for the treatment of neurodegeneration.
    Matched MeSH terms: Glutathione Peroxidase/metabolism
  13. Sidahmed HM, Abdelwahab SI, Mohan S, Abdulla MA, Mohamed Elhassan Taha M, Hashim NM, et al.
    PMID: 23634169 DOI: 10.1155/2013/450840
    Cratoxylum arborescens (Vahl) Blume is an Asian herbal medicine with versatile ethnobiological properties including treatment of gastric ulcer. This study evaluated the antiulcerogenic mechanism(s) of α -mangostin (AM) in a rat model of ulcer. AM is a prenylated xanthone derived through biologically guided fractionation of C. arborescens. Rats were orally pretreated with AM and subsequently exposed to acute gastric lesions induced by ethanol. Following treatment, ulcer index, gastric juice acidity, mucus content, histological and immunohistochemical analyses, glutathione (GSH), malondialdehyde (MDA), nitric oxide (NO), and nonprotein sulfhydryl groups (NP-SH) were evaluated. The anti-Helicobacter pylori, cyclooxygenase-2 (COX-2) inhibitory effect, and antioxidant activity of AM were also investigated in vitro. AM (10 and 30 mg/kg) inhibited significantly (P < 0.05) ethanol-induced gastric lesions by 66.04% and 74.39 %, respectively. The compound induces the expression of Hsp70, restores GSH levels, decreases lipid peroxidation, and inhibits COX-2 activity. The minimum inhibitory concentration (MIC) of AM showed an effective in vitro anti-H. pylori activity. The efficacy of the AM was accomplished safely without presenting any toxicological parameters. The results of the present study indicate that the antioxidant properties and the potent anti-H. pylori, in addition to activation of Hsp70 protein, may contribute to the gastroprotective activity of α -mangostin.
    Matched MeSH terms: Glutathione
  14. Tan GM, Lim HJ, Yeow TC, Movahed E, Looi CY, Gupta R, et al.
    Proteomics, 2016 05;16(9):1347-60.
    PMID: 27134121 DOI: 10.1002/pmic.201500219
    Chlamydia trachomatis is the leading causative agent of bacterial sexually transmitted infections worldwide which can lead to female pelvic inflammatory disease and infertility. A greater understanding of host response during chlamydial infection is essential to design intervention technique to reduce the increasing incidence rate of genital chlamydial infection. In this study, we investigated proteome changes in epithelial cells during C. trachomatis infection by using an isobaric tags for relative and absolute quantitation (iTRAQ) labeling technique coupled with a liquid chromatography-tandem mass spectrometry (LC-MS(3) ) analysis. C. trachomatis (serovar D, MOI 1)-infected HeLa-229 human cervical carcinoma epithelial cells (at 2, 4 and 8 h) showed profound modifications of proteome profile which involved 606 host proteins. MGST1, SUGP2 and ATXN10 were among the top in the list of the differentially upregulated protein. Through pathway analysis, we suggested the involvement of eukaryotic initiation factor 2 (eIF2) and mammalian target of rapamycin (mTOR) in host cells upon C. trachomatis infection. Network analysis underscored the participation of DNA repair mechanism during C. trachomatis infection. In summary, intense modifications of proteome profile in C. trachomatis-infected HeLa-229 cells indicate complex host-pathogen interactions at early phase of chlamydial infection.
    Matched MeSH terms: Glutathione Transferase/genetics; Glutathione Transferase/metabolism
  15. Do TD, Thi Mai N, Duy Khoa TN, Abol-Munafi AB, Liew HJ, Kim CB, et al.
    Evol Bioinform Online, 2019;15:1176934319853580.
    PMID: 31236006 DOI: 10.1177/1176934319853580
    Temperature is an abiotic factor that affects various biological and physiological processes in fish. Temperature stress is known to increase the production of reactive oxygen species (ROS) that subsequently cause oxidative stress. Fish is known to evolve a system of antioxidant enzymes to reduce ROS toxicology. Glutathione peroxidase (GPx) family consists of key enzymes that protect fish from oxidative stress. In this study, full-length GPx1 cDNA (GenBank accession no. KY984468) of Tor tambroides was cloned and characterized by rapid amplification of cDNA ends (RACE). The 899-base-pair (bp) GPx1 cDNA includes a 576-bp open reading frame encoding for 191 amino acids, plus 28 bp of 5'-untranslated region (UTR) and 295 bp of 3'-UTR. Homology analysis revealed that GPx1 of T tambroides (Tor-GPx1) shared high similarity with GPx1 sequences of other fish species. The phylogenetic construction based on the amino acid sequence showed that Tor-GPx1 formed a clade with GPx1 sequences of various fish species. Real-time polymerase chain reaction (PCR) was performed to assess the levels of GPx1 gene expression in the liver and muscle of T tambroides under thermal stress. The results indicated that GPx1 gene expression was down-regulated under decreased temperature. However, there was no significant difference between GPx1 gene expression in fish exposed to high temperature and control. Our study provides the first data regarding GPx gene expression in T tambroides under thermal stress.
    Matched MeSH terms: Glutathione Peroxidase
  16. Subermaniam K, Yow YY, Lim SH, Koh OH, Wong KH
    Saudi J Biol Sci, 2020 Jun;27(6):1435-1445.
    PMID: 32489279 DOI: 10.1016/j.sjbs.2020.04.042
    Oxidative damage has been associated with the pathophysiology of depression. Macroalgae are equipped with antioxidant defense system to counteract the effects of free radicals. We explored the use of Malaysian Padina australis to attenuate high dose corticosterone-mediated oxidative damage in a cellular model mimicking depression. Fresh specimen of P. australis was freeze-dried and extracted sequentially with hexanes, ethyl acetate and ethanol. The extracts were screened for their phytochemical contents and antioxidant activities. Ethanol extract demonstrated the most potent antioxidant capacity and was selected for subsequent assays against high dose corticosterone of 600 µM-mediated oxidative damage in the rat pheochromocytoma (PC12) cells. The corticosterone reduced the cell viability, glutathione (GSH) level, aconitase activity, and mitochondrial membrane potential (MMP); and increased the lactate dehydrogenase (LDH) release, intracellular reactive oxygen species (ROS) level and apoptosis. However, the extent of oxidative damage was reversed by 0.25-0.5 mg/mL ethanol extract suggesting a possible role of P. australis-based antioxidants in the mitochondrial defense against constant ROS generation and regulation of antioxidant pathway. The effects were similar to that of desipramine, a tricyclic antidepressant. Our findings indicate that P. australis can be developed as a mitochondria-targeted antioxidant to mitigate antidepressant-like effects.
    Matched MeSH terms: Glutathione
  17. Inayat-Hussain SH, Chan KM, Rajab NF, Din LB, Chow SC, Kizilors A, et al.
    Toxicol Lett, 2010 Mar 1;193(1):108-14.
    PMID: 20026395 DOI: 10.1016/j.toxlet.2009.12.010
    Goniothalamin (GTN) isolated from Goniothalamus sp. has been demonstrated to induce apoptosis in a variety of cancer cell lines including Jurkat T leukemia cells. However, the mechanism of GTN-induced apoptosis upstream of mitochondria is still poorly defined. In this study, GTN caused a decrease in GSH with an elevation of reactive oxygen species as early as 30 min and DNA damage as assessed by Comet assay. Analysis using topoisomerase II processing of supercoiled pBR 322 DNA showed that GTN caused DNA damage via a topoisomerase II-independent pathway suggesting that cellular oxidative stress may contribute to genotoxicity. A 12-fold increase of caspase-2 activity was observed in GTN-treated Jurkat cells after 4h treatment and this was confirmed using Western blotting. Although the caspase-2 inhibitor Z-VDVAD-FMK inhibited the proteolytic activity of caspase-2, apoptosis ensued confirming that caspase-2 activity was not crucial for GTN-induced apoptosis. However, GTN-induced apoptosis was completely abrogated by N-acetylcysteine further confirming the role of oxidative stress. Since cytochrome c release was observed as early as 1h without any appreciable change in Bcl-2 protein expression, we further investigated whether overexpression of Bcl-2 confers resistance in GTN-induced cytotoxicity. Using a panel of Jurkat Bcl-2 transfectants, GTN cytotoxicity was not abrogated in these cells. In conclusion, GTN induces DNA damage and oxidative stress resulting in apoptosis which is independent of both caspase-2 and Bcl-2.
    Matched MeSH terms: Glutathione/metabolism
  18. Bhattacharyya SP, Saha N, Wee KP
    Gene Geogr, 1989 Apr;3(1):21-6.
    PMID: 2487053
    Glutathione S-transferases (GST; E.C.2.5.1.18) were phenotyped by starch gel electrophoresis in post-mortem liver samples from 683 unrelated subjects of both sexes. 305 were Chinese, 185 Indians, 147 Malays and 46 from other racial groups of South-East Asia. GST1 and GST2 were found to be polymorphic in these populations. Additional alleles (GST1*3 and GST2*O) were observed at low frequency in all the ethnic groups. The frequency of GST1*1 was lower and that of GST1*2 was higher in Indians and Malays as compared to Chinese. GST1*0 and GST1*3 frequencies were similar in all these ethnic groups. The gene frequencies of the alleles of the GST2 locus varied significantly in the population studied. GST2*0 frequency was significantly higher in Indians than in Chinese and Malays, while the lowest frequency of GST2*1 was found in the Indians. GST2*2 frequency was higher in the Malays than in Chinese and Indians. GST1 and GST2 phenotype distributions were in agreement with Hardy-Weinberg equilibrium in all the ethnic groups studied. Sex made no significant difference in the phenotype distribution.
    Matched MeSH terms: Glutathione Transferase/genetics*
  19. Lie-Injo LE, Ganesan J, Clegg JB, Weatherall DJ
    Blood, 1974 Feb;43(2):251-9.
    PMID: 4810076
    Matched MeSH terms: Glutathione; Glutathione Reductase/metabolism
  20. Yamamoto T, Tsunematsu Y, Hara K, Suzuki T, Kishimoto S, Kawagishi H, et al.
    Angew Chem Int Ed Engl, 2016 05 17;55(21):6207-10.
    PMID: 27072782 DOI: 10.1002/anie.201600940
    Geometric isomerization can expand the scope of biological activities of natural products. The observed chemical diversity among the pseurotin-type fungal secondary metabolites is in part generated by a trans to cis isomerization of an olefin. In vitro characterizations of pseurotin biosynthetic enzymes revealed that the glutathione S-transferase PsoE requires participation of the bifunctional C-methyltransferase/epoxidase PsoF to complete the trans to cis isomerization of the pathway intermediate presynerazol. The crystal structure of the PsoE/glutathione/presynerazol complex indicated stereospecific glutathione-presynerazol conjugate formation is the principal function of PsoE. Moreover, PsoF was identified to have an additional, unexpected oxidative isomerase activity, thus making it a trifunctional enzyme which is key to the complexity generation in pseurotin biosynthesis. Through the study, we identified a novel mechanism of accomplishing a seemingly simple trans to cis isomerization reaction.
    Matched MeSH terms: Glutathione; Glutathione Transferase
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